∗ Apologies to Mark Hinchliff for stealing the title of his dissertation. (See Hinchliff, A Defense of Presentism. As it turns out, however, the version of Presentism defended here is different from the version defended by Hinchliff. See Section 3.1 below.).

This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

This paper analyzes the ontology and epistemology of time in Lucretius’ De rerum natura. It uses the physiology of perception as well as epistemology to shed new light on the metaphysics. It presents an exegesis-based interpretation of the nature of time and of its perception, both arguing for and refining this interpretation by showing its explanatory power. The paper shows that Lucretius represents the perception of time or sensus temporis as a distinct sensory faculty, reconstructs how it emerges and operates, (...) and relates it to his account of perception more generally. The sense of time in turn is seen to explain aspects of related faculties, including thought and sight, and cases of apparent simultaneity. The paper thus contributes to, among other things, our understanding of the speed of perception and Lucretius’ account of the nature of time itself — arguing that Lucretius represents time as both continuous (not atomic) and real, as well as something perceived. (shrink)

Opponents of presentism have often argued that the presentist has difficulty in accounting for what makes true past-tensed propositions true in a way that is compatible with her metaphysical view of time and reality. The problem is quite general and concerns not only strong truth-maker principles, but also the requirement that truth be grounded in reality. In order to meet the challenge, presentists have proposed many peculiar present aspects of the world as grounds for truths concerning the past, such as (...) uninstantiated haecceities, Meinongian non-existents, ersatz times, and dispositional and distributional properties. The main problem with all such solutions is that any explanation of what grounds a TptP that involves the past is eo ipso a better explanation than any that involves only the present. Thus, the quest for an account of grounding for TptP that is compatible with the presentist ontology and ideology is doomed to be explanatorily deficient with respect to eternalism. In a recent article, Ben Caplan and David Sanson have claimed that presentists should change their strategy and, rather than seeking for exotic grounds for TptP, should adopt a more liberal view of explanation. That is, they should allow themselves to resort to “past directed” explanations, even if they do not accept the past in their ontology and ideology. I argue that such a proposal is not compatible with the tenet that there is a substantial distinction between the ideology of such a version of presentism and that of eternalism. Therefore, the presentist cannot endorse such “deflationist” explanations as an easy way out to the problem of the grounding of TptP. (shrink)

I present a new problem for the tense realist concerning the evaluation of cross-temporal claims, such as ‘John is now taller than Michael was in 1984’. Time can play two different roles in the evaluation of an utterance of a sentence: either as an element that completes the content expressed by the utterance (the completion role), or as part of the circumstances against which the content is evaluated (the evaluation role). It is this latter role that time plays in the (...) realist view of tenses. I argue that if the content of a cross-temporal sentence is taken at face value (as an ascription of a crosstemporally instantiated relation), time does not play the evaluation role. Therefore, the world of the tense realist seems to leave no room for cross-temporality. (shrink)

Ostrich presentists maintain that we can use all the expressive resources of the tensed language to provide an explanation of why true claims about the past are true, without thereby paying any price in terms of ontology or basic ideology. I clarify the position by making a distinction between three kinds of explanation, which has general interest and applicability. I then criticize the ostrich position because it requires an unconstrained version of the third form of explanation, which is out of (...) place in metaphysics. (shrink)

In this paper I argue in favour of a new definition of presentism that I call ‘existence presentism’ (EP). Typically, presentism is defined as the thesis that ‘only present objects exist’, or ‘nothing exists that is non-present’.1 I assume these statements to be equivalent. I call these statements of presentism ‘conventional presentism’ (CP). First, in §2, I rehearse arguments due to Ulrich Meyer that purport to show that presentism is not adequately defined as CP. In §§2.1–2.4 I show that considerations (...) of the sort raised by Meyer infect attempts to define presentism, due to Thomas Crisp, Tom Stoneham, and Theodore Sider. Thus the first half of the paper is constituted by a negative project that looks to show how extant definitions of presentism fail. In the second half of the paper, I continue in the negative theme in §3, before laying out EP and demonstrating that it solves the problems faced by CP and offering explanations of how to make sense of certain key notions that lie at the heart of EP. I conclude that EP is preferable to CP. (shrink)

A. N. Prior; XIV—Time, Existence and Identity, Proceedings of the Aristotelian Society, Volume 66, Issue 1, 1 June 1966, Pages 183–192, https://doi.org/10.1093/.

According to four dimensionalism, the material world is divided into momentary stages. In a four-dimensional world, which objects are the ordinary things, the things we normally name and quantify over? Aggregates of stages, according to most four-dimensionalists, but according to stage theorists (or exdurantists), ordinary objects are instead to be identified with the stages themselves. (A temporal counterpart theoretic account of de re temporal predication is then given.) This paper argues that a stage theorist is best positioned to accept David (...) Lewis's argument from temporary intrinsics for four-dimensionalism, since stage theorists are the only four-dimensionalists who attribute monadic temporary intrinsic properties to ordinary things. (shrink)

Perry argues that certain sorts of indexicals are 'essential', in the sense that they cannot be eliminated in favor of descriptions. This paper also introduces the influential idea that certain sorts of indexicals play a special role in thought, and have a special connection to action.

How is the debate between presentism and eternalism to be characterized? It is usual to suggest that this debate about time is analogous to the debate between the actualist and the possibilist about modality. I think that this suggestion is right. In what follows I pursue the analogy more strictly than is usual and offer a characterization of what is at the core of the dispute between presentists and eternalists that may be immune to worries often raised about the substantiality (...) of the debate. I suggest that the debate be characterized in Lewisean terms and define positions I call *Lewisean* eternalism and anti-*Lewisean*' presentism (analogous to Lewisean possibilism and anti-Lewisean actualism). I explain some advantages of the proposal and discuss some objections. I conclude that pursuing the analogy strictly offers the prospect of giving clear sense to a controversy which otherwise seems to many deeply obscure. (shrink)

It is surprisingly hard to define presentism. Traditional definitions of the view, in terms of tensed existence statements, have turned out not to to be capable of convincingly distinguishing presentism from eternalism. Picking up on a recent proposal by Tallant, I suggest that we need to locate the break between eternalism and presentism on a much more fundamental level. The problem is that presentists have tried to express their view within a framework that is inherently eternalist. I call that framework (...) the Fregean nexus, as it is defined by Frege’s atemporal understanding of predication. In particular, I show that the tense-logical understanding of tense which is treated as common ground in the debate rests on this very same Fregean nexus, and is thus inadequate for a proper definition of presentism. I contrast the Fregean nexus with what I call the original temporal nexus, which is based on an alternative, inherently temporal form of predication. Finally, I propose to define presentism in terms of the original temporal nexus, yielding original presentism. According to original presentism, temporal propositions are distinguished from atemporal ones not by aspects of their content, as they are on views based on the Fregean nexus, but by their form—in particular, by their form of predication. (shrink)

This paper defends three theses: that presentism is either trivial or untenable; that the debate between tensed and tenseless theories of time is not about the status of presentism; and that there is no temporal analogue of the modal thesis of actualism.

The paper reviews Balashov’s Asymmetry Thesis concerning co-existing (point-sized) enduring objects, on the one hand, and perduring ones, on the other. In this regard, it becomes crucial to investigate whether, at a given spacetime point p, it is located only the respective temporal part of a perdur- ing whole, or that whole as well. Two alternatives ought to be distinguished and, then, I will argue as follows: If the perduring whole is located where its parts are, the original asymmetry- thesis (...) has to be rejected. If, however, the perduring whole is not located where its parts are, the spatiotemporal locations of the parts can no longer be used to ground the co-existence relation. But, with the modified co-existence relation the asymmetry between perdurantism and endurantism turns out to be even much stronger than it has been assumed. (shrink)

The important switch from the so-called old B-theory to the new tenseless theory of time (NTT), which had significant implications for the field of tense and indexicals, occurred after Carnap’s era. Against this new background, Carnap’s original inter-translatability thesis can no longer be upheld. The most natural way out would be to modify Carnap’s position according to the NTT; but this is not compatible with Carnap’s metaphysical neutrality thesis. Even worse, Carnap’s work on measurement theory can be used to develop (...) an argument in favour of the A-theory. I argue that there are tensed basic sentences which are needed in order to construct a tenseless system and thus cannot be translated without loss of meaning into tenseless ones (old B-theory) or made true by tenseless facts (NTT). (shrink)

There is a common form of problem, to be found in many areas of philosophy, concerning the relationship between our perspective on reality and reality itself. We make statements (or form judgements) about how things are from a given standpoint or perspective. We make the statement ‘it is raining’ from the standpoint of the present time, for example, or the statement‘it is here’ from the standpoint of where we are, or the statement ‘I am glad’ from the standpoint of a (...) subject. In each of these cases, the statement has a certain ‘aspect’ or perspectival character in virtue of which its truth is capable of varying from one standpoint to another. Thus the statement ‘it is raining’ is tensed, the statement ‘it is here’ is ‘spatiocentric’ and the statement ‘I am glad’ is first-personal. The problem we then face is to determine whether this aspect is a feature of the reality which is described or merely a feature of the statement by which it is described. Is reality itself somehow tensed or spatiocentric or firstpersonal or is it merely that we describe a tenseless or spatially uncentered or impersonal reality from a tensed or spatiocentric or first-personal point of view? (shrink)

Tenseless theorists assert that the relational structure of earlier/later is the essential structure of time. Using B-notions, so they think, we speak about time ‘as it is’ in a metaphysical sense and hence from the outside of our subjective perspective on it. I suggest on the contrary that the relational structure of earlier/later is part of our own intellectual structuring within the access to temporal phenomena. Furthermore it is essentially characterized by the structure of juxtaposition which originates in spatial experience (...) rather than in temporal. In order to show this I consult Henri Bergson’s analysis of our temporal experience on the one hand and of our intellectual practice on the other hand. I will conclude that it is not unplausible to take the relational account of time to be more closely connected to the nature of our intellect than to the nature of time itself. (shrink)

Throughout this century many philosophers and physicists have gone for thc ‘big ki11’ regarding tenses. They have tried to show via McTaggart’s paradox and special relativity that tcnscs arc logically and physically impossible, rcspcctivcly. Ncithcr attempt succccds, though as I argue, both lcavc their mark. In thc iirst two sections of thc paper I introduce some conceptual difficulties for the tensed theory of time. The next section then discusses the standing 0f tenses in light of special relativity, cspccially rcccnt work (...) by Stcin on thc topic. I argue that, Stcin’s possibility thcorcm notwithstanding, special relativity is inconsistent with any philosophicully interesting conception of tense. Finally, I search for help for tenses in the broader context of quantum theory, Lorcntzian interpretations 0f time dilation/length contraction, and gcncral relativistic spacctimcs. I suggest that these avenues d0 not provide tenses the home for which some have hoped. (shrink)

Four-dimensionalism is the thesis that everyday objects, such as you and me, are space-time worms that persist through time by having temporal parts none of which is identical to the object itself. Objects are aggregates or sums of such temporal parts. The main virtue of fourdimensionalism is that it solves—or does away with—the problem of identity through change.1 The main charge raised against it is that it is inconsistent with the thesis according to which there is change in the world.2 (...) If this charge could be sustained, then we would need compelling arguments in support of the view that things are four-dimensional, since the view that there is no change in the world conflicts with so many of our most well-supported common-sense beliefs. In what follows, however, I want to show that, contrary to what is usually believed, fourdimensionalism does not entail a changeless world. (shrink)

Four-dimensionalism is the thesis that everyday objects, such as you and me, are space-time worms that persist through time by having temporal parts none of which is identical to the object itself. Objects are aggregates or sums of such temporal parts. The main virtue of four-dimensionalism is that it solves—or does away with—the problem of identity through change. The main charge raised against it is that it is inconsistent with the thesis according to which there is change in the world. (...) If this charge could be sustained, then we would need compelling arguments in support of the view that things are four-dimensional, since the view that there is no change in the world conflicts with so many of our most well-supported common-sense beliefs. In what follows, however, I want to show that, contrary to what is usually believed, four-dimensionalism does not entail a changeless world. (shrink)

How do ordinary objects persist through time and across possible worlds ? How do they manage to have their temporal and modal properties ? These are the questions adressed in this book which is a "guided tour of theories of persistence". The book is divided in two parts. In the first, the two traditional accounts of persistence through time (endurantism and perdurantism) are combined with presentism and eternalism to yield four different views, and their variants. The resulting views are then (...) examined in turn, in order to see which combinations are appealing and which are not. It is argued that the 'worm view' variant of eternalist perdurantism is superior to the other alternatives. In the second part of the book, the same strategy is applied to the combinations of views about persistence across possible worlds (trans-world identity, counterpart theory, modal perdurants) and views about the nature of worlds, mainly modal realism and abstractionism. Not only all the traditional and well-known views, but also some more original ones, are examined and their pros and cons are carefully weighted. Here again, it is argued that perdurance seems to be the best strategy available. (shrink)

I examine the issue of persistence over time in thecontext of the special theory of relativity (SR). Thefour-dimensional ontology of perduring objects isclearly favored by SR. But it is a different questionif and to what extent this ontology is required, andthe rival endurantist ontology ruled out, by thistheory. In addressing this question, I take theessential idea of endurantism, that objects are whollypresent at single moments of time, and argue that itcommits one to unacceptable conclusions regardingcoexistence, in the context of SR. (...) I then propose anddiscuss a plausible account of coexistence forperduring objects, which is free of these defects. This leaves the endurantist room for some maneuvers. I consider them and show that they do not really helpthe endurantist out. She can accommodate the notionof coexistence in the relativistic framework only atthe cost of renouncing central endurantist intuitions. (shrink)

In a pair of very important papers, namely “Space, Time and Individuals” in the Journal of Philosophy for October 1955 and “The Indestructibility and Immutability of Substances” in Philosophical Studies for April 1956, Professor N. L. Wilson began something which badly needed beginning, namely the construction of a logically rigorous “substance-language” in which we talk about enduring and changing individuals as we do in common speech, as opposed to the “space-time” language favoured by very many mathematical logicians, perhaps most notably (...) by Quine. This enterprise of Wilson's is one with which I could hardly sympathize more heartily than I do; and one wishes for this logically rigorous “substance-language” not only when one is reading Quine but also when one is reading many other people. How fantastic it is, for instance, that Kotarbinski1 should call his metaphysics “Reism” when the very last kind of entity it has room for is things —instead of them it just has the world-lines or life-histories of things; “fourdimensional worms”, as Wilson says. Wilson, moreover, has at least one point of superiority to another rebel against space-time talk, P. F. Strawson; namely he does seriously attempt to meet formalism with formalism—to show that logical rigour is not a monopoly of the other side. At another point, however, Strawson seems to me to see further than Wilson; he is aware that substance-talk cannot be carried on without tenses, whereas Wilson tries to do without them. Wilson, in short, has indeed brought us out of Egypt; but as yet has us still wandering about the Sinai Peninsula; the Promised Land is a little further on than he has taken us. (shrink)

Suppose now that two philosophers, McX and I, differ over ontology. Suppose McX maintains there is something which I maintain there is not. McX can, quite consistently with his own point of view, describe our difference of opinion by saying that I refuse to recognize certain entities. I should protest of course that he is wrong in his formulation of our disagreement, for I maintain that there are no entities, of the kind which he alleges, for me to recognize; but (...) my finding him wrong in his formulation of our disagreement is unimportant, for I am committed to considering him wrong in his ontology anyway. When I try to formulate our difference of opinion, on the other hand, I seem to be in a predicament. I cannot admit that there are some things which McX countenances and I do not, for in admitting that there are such things I should be contradicting my own rejection of them. (shrink)

Presentism is the doctrine that only the present is real. Since ordinary talk and thought are full of quantification over non-present objects, presentists are in a familiar predicament: in their unreflective moments they apparently commit themselves to far more than their ontological scruples allow. A familiar response is to begin a project of paraphrase. Truths appearing to quantify over problematic entities are shown, on analysis, to not involve quantification over those entities after all. But I think that we might be (...) better off abandoning paraphrase altogether. I suggest a project of discovering “underlying truths” rather than paraphrases. I will explore this strategy as applied to defending presentism, but my hope is that lovers of desert landscapes everywhere will herein find words of comfort. (shrink)

Discussions of the nature of time, and of various issues related to time, have always featured prominently in philosophy, but they have been especially important since the beginning of the 20th Century. This article contains a brief overview of some of the main topics in the philosophy of time — Fatalism; Reductionism and Platonism with respect to time; the topology of time; McTaggart's arguments; The A Theory and The B Theory; Presentism, Eternalism, and The Growing Universe Theory; time travel; and (...) the 3D/4D controversy — together with some suggestions for further reading on each topic, and a bibliography. (shrink)

Traditionally, this puzzle has been solved in various ways. Aristotle, for example, distinguished between “accidental” and “essential” changes. Accidental changes are ones that don't result in a change in an objects' identity after the change, such as when a house is painted, or one's hair turns gray, etc. Aristotle thought of these as changes in the accidental properties of a thing. Essential changes, by contrast, are those which don't preserve the identity of the object when it changes, such as when (...) a house burns to the ground and becomes ashes, or when someone dies. Armed with these distinctions, Aristotle would then say that, in the case of accidental changes, (1) and (2) are both false—a changing thing can really change one of its “accidental properties” and yet literally remain one and the same thing before and after the change. (shrink)